Pollution threatening groundwater supplies, EA warns

Most of England's groundwater is at risk from agricultural fertilisers, pesticides, solvents and other contaminants, the Environment Agency has said in its first groundwater assessment report.

Worsening groundwater quality is a concern at 81% of sites in England and 35% in Wales, the EA warns in the Underground, under threat report published this week.

Growing demand is the other serious strain on aquifers, alongside pollution from farms, industry and landfill sites diffusing into the soil and surface waters and entering underground supplies.

Urbanisation aggravates the situation with higher demand and pollution levels, and less scope for recovery. These problems are likely to worsen in coming years, the agency warned.

Groundwater supplies over 70% of drinking water in the dry south-east region and as much as a third in England. Across England and Wales 16m people get their tap water from ground sources. And England, with rising temperatures and more frequent droughts, will be increasingly forced to rely on groundwater as surface water levels fall and pollutants become concentrated.

Groundwater quality is declining rapidly, the EA warned. Pollution has led to 146 sources becoming unusable over the last 30 years, cutting off sources that would produce 425,000 cubic litres daily - enough to supply 30m people.

These losses translate into Groundwater is worth £8bn to the UK economy, the EA estimates. Problems with pollution and rising demand have cost the UK economy £754m over the 30 year period, the agency said.

The Environment Agency's environment protection director Tricia Henton said: "To many of us, groundwater is out of sight and out of mind. But this hidden resource, which provides clean, fresh water for our homes, industry, agriculture and the environment, is a limited resource that must be properly managed and protected."

"Groundwater is very vulnerable to pollution and while it takes just a few careless moments to pollute or contaminate, it can take decades or even centuries to recover. That's why we need to do what we can to stop it from being polluted in the first place."

The environment agency's "risk-based approach" to groundwater protection involves banning activities that could pollute groundwater within Special Protection Zones (SPZs) marked out around groundwater sources.

Alongside the State of the Environment report on groundwater, the first edition to focus on the issue, the Environment Agency issued a consultation regarding its policy on groundwater.

The agency is calling on water companies and all other interested parties to feed back on the issues they want to see addressed, with the process launched at a conference in London this week.

Concerns raised at the conference included the potential pitfalls of the risk-based approach, which could lead to unrecognised risks coming to haunt us later as was the case with PFOS, the chemical that entered water resources following the Buncefield explosion.

Some also felt that the agency's approach did not recognise the importance of groundwater for eco-systems, and that it "shouldn't all be about drinking water."